Process for producing prints and dyeings with ester salts of leuco vat dyestuffs



Patented Mar. 12, 1940 PATENT OFFICE PRQCESS FOR PltODUCING PRINTS AND DYEINGS WITH ESTER SALTS 0F LEUGO VAT DYESTUFFS Ernst Tschan, Basel, Switzerland, assignor to the firm Durand & Huguenin S. A., Basel, Switzerland No Drawing. Application October 25, 1937, Se-

rial 1936 5 Claims.

The method for printing and dyeing with ester salts of leuco vat dyestuffs consists in applying these bodies in the form of watery solutions, bringing the solutions onto the fibre and subjecting the same to an acid oxidation, whereby the vat dyestuff is regenerated in a very fine division and so that the dyeing is developed.

The color can be developed by means of special developing baths (see U. S.'A. Patent 1,575,958). The development can also be carried out by steaming with the aid of an appropriate oxidizing agent in the presence of a substance yielding acid in the heat (see U. S. A. Patent 1,747,107)

According to the process described in British Patent 356,577, aluminium chlorate, which acts at the same time as oxidizing and as acid yielding agent, and which enables the development of colors of leuco ester salts also without steaming, is used. To this effect, the goods are at first padded with a solution of tartaric acid and ammonium vanadate, and dried. Then they are printed with a printing color containing a leuco ester salt and aluminium chlorate. Finally, development is effected by simply hanging the goods at room temperature. I

It has now been found that this process can be simplified by printing or padding the goods with a color containing a leuco ester salt, ammonium chlorate and ammonium vanadate or ammonium chlorate, ammonium persulphate and ammonium vanadate, the latter being added as a catalyst. Ammonium persulphate is employed in addition to ammonium chlorate in cases where the ester salts of leuco vatdyestufis used are developed only with difficulty. Here also the development of the color is operated by simply hanging the goods at an ordinary or slightly raised temperature. But in this case, the pre-treatment of the fibre, that is to say the padding of the same with a solution of tartaric acid and ammonium vanadate before applying the printing color, is not necessary;

This new method, whereby the pre-treatment of the goods can be dispensed from, represents No. 170,991. In Germany October 26,

a real improvement, compared with the processes applied so far. I

The new process is especially suitable for cotton printing. tain neither copper, nor any other heavy metal salts, which might attack the doctor or lead to some other trouble. Besides, the colors have a goods stability, and the shades obtained in this way are well developed. I g

The new process may also be used forpadding, whereas the process applied hitherto was only suitable for printing purposes. y

The persulphuric acid and the chloric acid can be used in the form of any other soluble salt, Without influencing the effect, so long as the formation of the ammonium salts of such acids in the printing paste or in. the padding liquor is guaranteed (e. g. sodium chlorate and ammonium chloride).

The following examples may illustrate the new process, the parts being by weight:

The printing colors do not con- Examples l 2 3 4 5 6 At 50 C. are added:

Solution of ammonium chlorate (15 B.) 4 After cooling down a solution is added containing: I

1 part of ammonium persulp ate 1 part ofammonia 4 2 2 2 parts of water Solution of ammonium vanadate 2 Ethylene-thioglycol 6 5 l0 5 6 10 Phenol 5 5 5 5 Urea 5 5 5 5 Hot water 23 25 7 21 28 13 Starch-tragacanth thickening 60 50 50 50 5D 50- Examples 7 8 9 10 11 12 7 Estersalt of leuco-4:4-dimethyl- 6:6-dichloro-thioindigo G 8 Estersclt of leuco-7:7-dimethyl- 6:6-dichloro-tl1ioindigo 6 9 Esterszilt of leuco-7:7-dimethyl- 5:Mdichloro-thioindigo 10 Ester-salt of leuco-5:6:7-trichlorothio-naphthcne-5:7-dicl1loro-indole-indigo ll Estcrsalt of leuco-2-nnthracene-2- indole-dibromindigo 12 Estersalt of leuco-4:5:7:4:5:7-hcx abromindigo Ethylclnethioglycoh At 50 G. are added:

Solution of ammonium chlorate (15 Be.) 15 12 15 15 8 8 After cooling down a solution is added containing:

1 part of ammoniiun persulphate 1 part of ammonia (20%) 4 4 4 -l -i 4 2 parts of water Solution of ammonium vanadatc Examples A 13 l4 l5 16 17 18 Estersalt of leuco-5:7:57-tctrabromindigo 5 Ester-salt of leuco-5-bromindigo Estersalt oileucoindigo 5 Estersalt of leucodimethoxy-dibenzanthrone 8 Estersalt of leucobromo-l-chloro- 2:3-naphthindole-2:2-p-methoxynaphthalene-indigo Estersalt oi the leuco-vat dyestuli from ix-isatinanilide and l-methyl'7:S-oxybenzoearbazole Ethylenetliioglycol i. 5 P enol Starch tragacanth thickening At 50 C. are added:

Solution of ammonium chlorate (15 Be.) After cooling down a solution is added containing:

1 part of ammonium persulphate 4 4 4 1 part ammonia (20%). 2parts of water Solution of ammonium vanadate 1 Ammonia (20%) i i 0.. 0.5 s.- .N.

Example 19 The material to be dyed is padded in a bath containing:

Parts Estersalt of leuco-4:4-dimethyl-6:6'-dichloro-thioindigo 20 Ethylenethioglycol 100 Phenol 50 Urea 50 Hot water 580 Tragacanth thickening 50 At 50 C. are added:

Solution of ammonium chlorate (15 B.)

After cooling down a solution is added containing: 1 part of ammonium persulphate 20 2 parts of water Solution of ammonium vanadate (l%) 50 After padding, the material is dried and developed, as described in the above printing processes.

What I claim is:

l. A process for producing prints or dyeings by means of ester salts of leuco vat dyestuffs, comprising applying on the goods, without pre-treatment thereof, a dye composition that contains, besides the leuco ester salt of the vat dyestuii, ammonium chlorate and ammonium vanadate, the latter being added as catalyst, and then developing the color by hanging the goods at ordinary or slightly increased temperature.

2. A process for producing prints or dyeings by means of ester salts of leuco vat dyestuffs, comprising applying on the goods, without pretreatment thereof, a dye composition that contains, besides the leuco ester salt of the vat dyestufi, ammonium chlorate, ammonium persulphate and ammonium vanadate, the latter being added as catalyst, and then developing the color by hanging the goods at ordinary or slightly increased temperature.

3. A process for producing prints or dyeing-s by means of ester salts of leuco vat dyestuffs, comprising applying on cotton goods Without pretreatment thereof, a dye composition that contains, besides the leuco ester salt of the vat dyestufi, ammonium chlorate, ammonium persulphate and ammonium vanadate, the latter being added as catalyst, and then developing the color by hanging the cotton goods at ordinary or slightly increased temperature.

t. A process for producing prints or dyeings by means of ester salts of leuco vat dyestuffs, comprising applying on the goods, without pretreatment thereof, a dye composition that contains the ester salt of leuco-dibenzpyrenequinone, ammcnium chlorate and ammonium vanadate, the late being added as catalyst, and then developing the color by hanging the goods at ordinary or slightly increased temperature.

5. A process for producing prints or dyeings by means of ester salts of leuco vat dyestuffs, comprising applying on the goods Without pretreatment thereof, a dye composition that contains the ester salt of leuco-dibromo-dibenzpyrenequinone, ammonium chlorate, ammonium persulphate and ammonium vanadate, the latter being added as catalyst, and then developing the color by hanging the goods at ordinary or slightly increased temperature.

ERNST TSCHAN. 

